Sharp nanothorn-equipped ionogel microrobots for targeted periodontitis therapy

Periodontitis necessitates targeted therapy due to its high prevalence, progressive tissue destruction, and systemic disease links. Conventional mechanical debridement and pharmacological treatments are limited by complex periodontal barriers, including viscous crevicular fluid and resilient biofilms, which impede bacterial eradication and drug delivery. Here, we engineered magnetically actuated microrobots with gold nanothorns for disrupting biofilms and penetrating mucus barriers. Fabricated by encapsulating curcumin in antibacterial ionogel microspheres with asymmetric magnetic deposition and nanothorn functionalization, these microrobots enabled precise magnetic navigation in viscous media, while penetrating a biomimetic mucus analog, enhancing periodontal retention, and mechanically dislodging biofilms. Furthermore, ethanol-responsive release of curcumin enhanced its bioavailability, thereby scavenging free radicals and modulating macrophage phenotypes to alleviate inflammation. Guided by a toothbrushing-inspired handheld magnetic controller, microrobots evaluated using in vivo murine models demonstrated reduced inflammation, inhibited bone resorption, improved tissue health, and oral microbiota remodeling toward ecological balance, showing promise for targeted periodontitis therapy.